Coal Combustion Residue True Cost Investigation

 

There are speeches by both Black & Veatch and SEFA at Power-Gen  relative to beneficially using ponded flyash. Burns & McDonnell has a stand and a meeting with Patricia Scroggin Wicker is scheduled. It will be an open discussion for any attendee. It is scheduled for 2 PM on Tuesday but check updates for changes.  Patricia was interviewed on this subject two years ago.

Meeting the new ELG and CCR requirements- options explained by Patricia Scroggin

Patricia Scroggin, currently a regional practice manager at Burns & McDonnell, explained the options for meeting the CCR and ELG requirements. Bottom ash choices include: the remote chain conveyor which does not require modifications at the boiler but is high in capital cost, and the Magaldi dry cooler which has the advantage of being a dry system but can provide a problem in trying to locate it under the boiler. The pneumatic ash extractor, dewatering bin, geotextile tubes and other options are also available. FGD wastewater options include both biological and physical chemical treatment. The vaporation option results in zero liquid discharge. Zero valent iron is an emerging technology.

Presentation: http://www.mcilvainecompany.com/Decision_Tree/subscriber/Tree/DescriptionTextLinks/Powergen_Scroggin_Presentation.pdf

Recording: http://home.mcilvainecompany.com/index.php/component/content/article?id=1216

 

Utility E Alert CCR  Excerpts – June to October 2019

 

October 11

 

EPA has  October 2019 Hearing  on Proposed Toxic Coal Ash Rollback

 

EPA held a public hearing on its latest proposal to roll back health and safety standards for coal ash.

 

A landmark rule in 2015 established the first-ever federal safety standards for this waste. But in response to coal industry lobbying, a new Trump proposal would create exemptions for two common methods of coal ash disposal: the creation of uncontained piles of waste, and the reuse of ash as fill in construction projects.

 

There was testimony opposing the roll back. “The proposed rule changes, which would weaken requirements for coal ash waste piles and the use of coal ash in construction projects, fail to meet the protective standard of RCRA section 4004(a). They are also arbitrary and capricious and without a rational basis because they ignore science.

 

The rule lacks any rational justification for removing the waste pile safeguards established in the 2015 coal ash rule. In fact, it directly contradicts the findings that EPA made when it developed that rule.

 

The proposal allows waste piles of substantial size to remain in place for significant periods of time without meeting any meaningful control standards to prevent harmful releases of coal ash to air, water, and soil. The rule would not require that waste be removed from the pile according to any set timetable. As long as the waste is eventually removed, even if that occurs years or even decades in the future, the rule would consider the pile to be “temporary storage” with no size limits, monitoring requirements, siting restrictions, or any other specific enforceable pollution control requirements.

 

The proposed rule is also unjustified in failing to prohibit unlined deposits of coal ash in inherently dangerous areas. A wealth of evidence, including monitoring data generated pursuant to the 2015 rule, indicates that unlined deposits of ash can leach toxic substances into groundwater.

 

Coal ash should not be placed into the environment at all, but if it is, EPA must adopt more stringent locational criteria regarding the placement of coal ash, including distance from the uppermost aquifer and proximity to unstable areas, floodplains, and seismic impact zones. Placement at those sites must be prohibited if those stringent criteria are not met.”

 

October 4

EPA Coal Ash Proposal: Unwarranted Mission Creep that will Harm Recycling

American Coal Ash Association representatives appearing at a U.S. Environmental Protection Agency public hearing this week will testify that the agency's proposal for revising coal ash regulations will erect significant barriers to safely recycling coal ash.

"EPA's proposals related to the definition of coal ash beneficial use are the opposite of a regulatory roll-back," said Thomas H. Adams, ACAA Executive Director. "Without any damage cases or scientific analysis to justify its actions, the agency is seeking to impose burdensome new restrictions that will cause millions more tons of material to be disposed rather than be used in ways that safely conserve natural resources and energy."

"The problem with EPA's beneficial use definition was that it contained a math error," said Adams. "But instead of simply fixing the math error, EPA is now proposing unjustified and sweeping changes to the definition that will have the effect of discouraging recycling. EPA is proposing to vastly expand the number of beneficial use activities that must be evaluated on a project by project basis and the recordkeeping that must accompany legitimate recycling activities. People won't do it. They'll just let the materials go to the landfill instead."

 

Georgia Power continues to make Progress on Ash Pond Closure at Plant McIntosh with Dewatering Process to begin this Month

 

Georgia Power continues to make progress towards the closure of the ash pond at Plant McIntosh with the dewatering process scheduled to begin this month. Dewatering marks a significant step towards completing the closure process, and Georgia Power's ash pond closure plan for Plant McIntosh is specifically designed for the site to ensure water quality is protected every step of the way.

 

The ash pond at Plant McIntosh will be completely excavated, with the ash stored in a permitted, lined landfill on plant property. Ash pond closures are site-specific and consider multiple factors, such as pond size, location, geology and amount of material; and each closure is certified by a team of independent, professional engineers.

 

"As we begin the dewatering process at Plant McIntosh, we are pleased with the progress we have made on our ash pond closures at all of our plants," said Dr. Mark Berry, vice president of Environmental & Natural Resources for Georgia Power. "We continue to focus on safety and meeting all compliance requirements throughout the process to fulfill our longstanding commitment to protect the environment and local communities. We have invested in water treatment systems to help ensure that our dewatering process is protective of the Savannah River. Throughout the process, clear communication to our customers and the community about our progress remains a priority."

 

The ash pond dewatering plan for Plant McIntosh has been approved by the Georgia Environmental Protection Division (EPD) and describes the water treatment system, controls and monitoring that will be used during the process to help ensure that the water discharged is protective of water quality standards. The planned on-site closure methods are being permitted and regulated by the EPD.

 

Communication regarding the closure plan is provided through EPD permitting notifications as well as posting on Georgia Power's website.

 

Georgia Power's ash pond closure plans fully comply with the federal CCR rule, as well as the more stringent requirements of Georgia's state CCR rule. Georgia was one of the first states in the country to develop its own rule regulating management and storage of CCR such as coal ash. The state rule, which goes further than the federal rule, regulates all ash ponds and CCR landfills in the state and includes a comprehensive permitting program through which the EPD will approve all actions to ensure ash pond closures are protective of water quality.

 

Today, more than 75 percent of the coal ash Georgia Power produces is recycled for various beneficial uses, such as Portland cement, concrete and cinder blocks.

 

August 23

 

TVA plans to expand Coal Ash Dry Storage Landfill for Kingston Fossil Plant

 

The Tennessee Valley Authority is moving forward with plans to expand the boundaries of an onsite dry storage landfill for coal combustion residuals at Kingston Fossil Plant near Harriman, Tennessee.

 

TVA currently operates a permitted state-of-the-art dry landfill on TVA property at Kingston for coal ash and gypsum, which is produced by the air emissions controls at the plant.

 

The landfill is designed for two phases, the first of which has been in operation since 2015. TVA is proposing to expand the boundary of the construction support area for the onsite gypsum landfill by an additional 21 acres to prepare for the next phase of the landfill. This additional land would be used as a staging area for equipment and as a source of clay borrow material, which will be used in the construction of a new phase of the landfill.

 

The Kingston Fossil Plant itself has been in operation since 1955. Its nine coal-fired units have a total capacity of about 1,400 MW, according to the TVA.

 

In 2008, a dike at the Kingston coal ash pond collapsed and is considered by some to have caused the worst coal ash disaster in U.S. history. Some 1.1 million gallons of coal ash slurry spilled out into the Emory River and onto surrounding land, damaging structures.

The TVA spent more than $1 billion on its Kingston coal ash cleanup.

 

The TVA has completed an amended supplemental Environmental Assessment that explains the expansion of the support area and considered the potential impacts. The final document and associated materials are available for review at www.tva.com/nepa.

 

TVA already has a construction permit for the next phase of the landfill. However, TVA has applied for other required permits through the Tennessee Department of Environment and Conservation, which includes a public hearing and comment period. 

 

August 4

 

Indian Coal Ash Dam collapses

 

The coal ash dam at Essar Energy’s 1,200 MW Mahan coal-fired power plant in Madhya Pradesh has collapsed inundating surrounding agricultural land and damaging the crops of up to 500 farmers. The Mahan coal-fired power plant is in Singrauli district which hosts 10 coal-fired power stations with a combined capacity of 21,000 MW. A local official stated that “initial investigations reveal that there was negligence on the part of the power company.” However, Essar Energy stated in a media release that the dam failed due to “sabotage” but did not provide any credible evidence to support its claim.

 

B&W New Bottom Ash Conveyor is Cost-effective approach to meet ELG Guidelines

 

The challenge to effectively and reliably meet regulatory targets for bottom ash handling has often required plant operators to make significant investments in equipment modifications. Babcock & Wilcox (B&W) set out to develop a new conveyance technology that not only met effluent limitation guidelines (ELG) and coal combustion residuals (CCR) requirements, but also considered unique plant layouts in providing a simplified and more cost-effective solution. The result? B&W has developed, patented and proven its Allen-Sherman-Hoff® Submerged Grind Conveyor (SGC) system, which offers maximized results and minimized modifications to the existing footprint.

 

Benefits

•         Reuse of existing water-sluice system’s key components reduces installation costs for retrofit

•         Reuse of existing bottom hoppers protects conveyor from impact of slag falls

•         Capability for redundancy, allowing for uninterrupted power if one chain conveyor string is out of service

•         Minimized outage time

•         Low profile, small footprint

•         Improved fuel efficiency and emissions control from water-filled ash collection hopper and supported water seal, which is designed to optimize O2 levels and minimize NOx

•         Low-wear, compact mechanical conveyor system reduces material costs

•         Low auxiliary power requirements

•          Low maintenance costs

New Water Management to help TVA deal with Coal Ash Processing

 

The Tennessee Valley Authority is touting a newly operational treatment plan to reduce its land footprint for dealing with coal ash at its six-decade-old, coal-fired Gallatin Fossil power plant in Sumner County.

A new water management system for coal combustion residuals (CCRs) will reduce the footprint from 435 acres to as few as three, according to the TVA. The federal energy entity says the new system is a step forward from traditional wet ash handling to dry handling and storage landfill.

 

TVA implemented the system last month, project manager Michael Clemmons noted. The flow management system treats plant process water to remove contaminants such as grease, oil and total suspended solids.

“Until now, Gallatin has utilized a 435-acre ash pond complex to slow treat water compared to the less than three acres of new water treatment tanks, which can treat a maximum flow of 43 million gallons a day,” Clemmons added.

 

Since 2016, Gallatin has stored dry CCR produced by the Gallatin scrubber in a lined, state-of-the-art 52-acre landfill, but process water and bottom ash was still treated in the ash pond complex. In an effort to move to completely dry storage, the new flow management system will treat the water and temporarily dewater bottom ash (until a permanent dewatering system comes online later this year), replacing the need for an ash pond.

“This flow management system fulfills our commitment at Gallatin to transition from wet to dry CCR handling and storage, which is cleaner, safer and more stable,” Clemmons said. 

 

The system complies with the EPA’s CCR Rule and positions TVA to fulfill the recent agreement between TVA and the Tennessee Department of Environment and Conservation to close the ash pond complex at Gallatin by removal of legacy CCR. 

 

“I’m proud of our team,” Scott Turnbow, vice president of civil projects, said. “Meeting our commitment on CCR is one of the many ways we serve the people of the valley as good stewards of the environment.” 

Gallatin’s 976 MW of coal-fired units were built and commissioned in the 1950s. A selective catalytic reduction system to reduce nitrogen oxide emissions and scrubbers to reduce sulfur dioxide emissions were installed on all four Gallatin units in 2016.

 

A lawsuit was filed in 2015 alleging bad coal ash disposal practices at the site. The TVA settled with the Tennessee Department of Environment and Conservation earlier this year, with the utility promising to remove 12 million cubic yards of CCR.

https://www.power-eng.com/articles/2019/07/new-water-management-to-help-tva-deal-with-coal-ash-processing.html

 

TVA investing in many Projects to meet CCR Requirements

 

Plans have been made for each coal plant with various alternatives depending on changes in the regulations. Details on the plans for each plant are provided.

 

https://www.tva.com/Environment/Environmental-Stewardship/Environmental-Reviews#coalgas

 

TVA planning to install FGD Wastewater Treatment Plant at Cumberland

TVA has issued a Final EA and FONSI for the proposed construction of wastewater treatment facilities at the Cumberland Fossil Plant (CUF). The treatment is for wet flue gas desulfurization (WFGD) wastewater.

TVA’s preferred alternative is Alternative 2 – Construct Wastewater Treatment System, Stages A & B (described below) and optimize selenium removal to the extent practical to establish site-specific selenium and nitrate/nitrite limits. This alternative would meet the purpose and need of the project. TVA acknowledges that Alternative 2 would not likely enable TVA to meet the limits on selenium and nitrate/nitrate currently set in the NPDES permit issued for CUF, which incorporates the limits promulgated in the 2015 ELG Rule. However, as noted above, EPA is reconsidering that rule, and TVA’s application for alternative limits based on fundamentally different factors is still pending. To the extent that the reconsidered rule and/or EPA’s decision on TVA’s fundamentally different factors application require more treatment than is contemplated under Alternative 2, TVA would reconsider its preferred alternative to enable compliance with the requirements.

  • Stage A includes installing the equipment necessary for WFGD wastewater treatment solids removal and dewatering. Stage A is expected to be completed as soon as September 2020. Gypsum fines removed during this stage will go to an on-site landfill.
  • Stage B includes the physical-chemical wastewater treatment steps necessary to remove dissolved and particulate metals such as arsenic and mercury from process flows. This stage represents the expected minimum treatment requirement resulting from EPA’s review of the ELGs. Certain components could be shared between stages. For example, clarifiers may be part of both Stage A and Stage B.

 

TVA Plan would close Bull Run Main Ash Pond with an Interim Cover

 

In accordance with the National Environmental Policy Act (NEPA), TVA has released a Final Supplemental Environmental Assessment (EA) and Finding of No Significant Impact (FONSI) for the Bull Run Fossil Plant (BRF) Ash Impoundment Closure project. The purpose of the proposed action is to support the implementation of TVA’s stated goal to transition from wet to dry storage of CCR at its coal plants by closing the Main Ash Impoundment and Stilling Pond at BRF, and to assist TVA in complying with state and federal requirements such as the National Pollutant Discharge Elimination System (NPDES) permit, and the U.S. Environmental Protection Agency’s (EPA) CCR Rule. This project would support a long-term need for wastewater treatment at BRF by providing a facility for processing non-CCR wastewater in the near-term and storm water in the long-term.

 

TVA’s preferred alternative is Alternative C, under which the Main Ash Impoundment would be Closed-in-Place with an interim cover and a portion (approximately 13 acres) would be repurposed for use as an interim process water basin. The Stilling Pond would be Closed-by-Removal and would also be repurposed for use as a process water basin. The interim solution for the Main Ash Impoundment would be implemented until a decision on a permanent solution for a disposition of the underlying CCR is made through the 2015 TDEC Commissioner’s Order process.

The alternatives presented in the Supplemental EA are as follows:

  • Alternative A – No Action
  • Alternative B – Closure-in-Place of a Portion of the Main Ash Impoundment, Closure-by-Removal of the Remaining Portion of the Main Ash Impoundment and Repurposing into a Process Water Basin, Closure-by-Removal of the Stilling Pond and Repurposing into a Process Water Basin, and Development of a Process Water Basin Emergency Spillway
  • Alternative C (Preferred Alternative) – Interim Cover of the Main Ash Impoundment and Repurposing a Portion for an Interim Process Water Basin, Closure-by-Removal of the Stilling Pond and Repurposing into a Process Water Basin, and Development of a Process Water Basin Emergency Spillway

BHE has aggressive Program to comply with Coal Combustion Residuals (CCR) requirements

PacifiCorp has 6 active surface impoundments and 4 active landfills; 3 inactive surface impoundments are undergoing closure.

MidAmerican Energy operates 2 active surface impoundments and 4 active landfills. In addition, MidAmerican Energy has 6 inactive surface impoundments; 5 have been closed, and 1 is continuing closure activities

NV Energy operates 2 active evaporative surface impoundments and 2 active landfills; all other surface impoundments are undergoing closure by removal.

MidAmerican Energy Company, NV Energy and PacifiCorp posted the results of their groundwater detection monitoring on March 1, 2018, in advance of the required posting under the CCR rule.

  • The ash ponds operated by the BHE companies are structurally sound and do not pose a risk to public safety.
  • The majority of the groundwater monitoring results are consistent with naturally occurring substances, do not exceed standards for action and do not threaten drinking water or human health; however, some testing results require additional assessment or action
  • The companies are working with their states and other agencies to evaluate the groundwater results to identify and take actions that meet or exceed all applicable requirements and are consistent with our environmental respect principles. This may include action to close ash ponds and implement alternative disposal methods.

Georgia Power continues to Make Progress towards the Closure of Seven Ash Ponds at Plant Yates with the Dewatering Process

 

Dewatering marks a significant step towards completing the closure process, and Georgia Power's ash pond closure plan for Plant Yates is specifically designed for the site to help ensure water quality is protected every step of the way.

Four of the ash ponds nearest the river at Plant Yates are to be completely excavated with the ash consolidated at the remaining three ponds, which will be closed in place using advanced engineering methods and technologies. Ash pond closures are site-specific and consider multiple factors, such as pond size, location, geology and amount of material; and each closure is certified by a team of independent, professional engineers.

"As we begin the dewatering process at Plant Yates, we are pleased with the progress we have made on our ash pond closure process throughout the state at all of our plants," said Dr. Mark Berry, vice president of Environmental & Natural Resources for Georgia Power. "We continue to focus on safety and meeting all compliance requirements throughout the process to fulfill our longstanding commitment to protect the environment and local communities. We have invested in appropriate water treatment systems to help ensure that our dewatering process is protective of the area's rivers. Throughout the process, clear communication to our customers and the community about our progress remains a priority."

The ash pond dewatering plan for Plant Yates that has been approved by the Georgia Environmental Protection Division (EPD) identifies the enhanced water treatment system, controls and monitoring that will be used during the process to help ensure that the water discharged is protective of water quality standards. The planned on-site closure methods will be permitted and regulated by the EPD.

To date, the company has removed two of the seven ash ponds at Plant Yates, completed engineering and feasibility studies and filed permit applications with the EPD for the remaining ash ponds on site. Communication regarding the closure plan is provided through EPD notifications, advance public notice of permits and updates to local homeowners and local media.

Georgia Power first announced its plans to permanently close all of its ash ponds in September 2015, with initial plans released in June 2016. The company is in the process of completely excavating 19 ash ponds located adjacent to lakes and rivers with the remaining 10 being closed in place using advanced engineering methods and closure technologies.

In November 2018, Georgia Power completed the submission of 29 Coal Combustion Residuals (CCR) permit applications as required by the Georgia CCR rule for ash ponds and landfills. These permit applications outlined significant and detailed engineering information about Georgia Power's ash pond closure plans and landfill operations plans. The permitting application process was developed and completed with significant internal and external resources supported by multiple third-party consulting and engineering firms.

Georgia Power's ash pond closure plans fully comply with the federal CCR rule, as well as the more stringent requirements of Georgia's state CCR rule. Georgia was one of the first states in the country to develop its own rule regulating management and storage of CCR such as coal ash. The state rule, which goes further than the federal rule, regulates all ash ponds and landfills in the state and includes a comprehensive permitting program through which the EPD will approve all actions to ensure ash pond closures are protective of water quality.

In 2016, the company announced that all ash ponds will stop receiving coal ash in three years and the significant construction work necessary to accommodate the dry-handling of ash is on track to be completed in 2019. Today, more than 60 percent of the coal ash Georgia Power produces is recycled for various beneficial uses, such as Portland cement, concrete and cinder blocks. 

Coal as an Ore

The cost to beneficiate most ores is very high. The equipment and energy consumption to convert large lumps into fine particles is significant. Other steps, such as acid leaching,  require purchase of chemicals and investment in mixers and other process equipment. Coal-fired power plant combustion can be viewed as a very cost-effective beneficiation process. It delivers very fine particles and the HCl needed for leaching while at the same time generating power rather than consuming it.

There is a very good argument to be made that the power plant should be designed and operated as a beneficiation process and that power generation would be the byproduct or only one of the main products.

With this in mind, the first design requirement is to select fuels (coal, petroleum coke, others), which will yield the maximum amount of product. This would include coals high in  sulfur, chlorine, rare earths, other metals, and ash with the most value. The second design requirement is how to most efficiently beneficiate the ore. It is likely that the process will be mostly a wet one.  The initial particulate collector (fabric filter or precipitator) will be eliminated. A series of two or more rod deck scrubbers will be used for the primary beneficiation. A tail-end wet precipitator will meet any particulate emission standards. Since wet scrubbers can handle low temperatures and acid mist, the heat exchanger can be designed to maximize energy recovery from the flue gases. The end products are power, pristine flyash, rare earths, other valuable metals, hydrochloric acid, sulfur, sulfuric acid or gypsum.

There is no scale-up problem. The process is already being used in many waste-to-energy plants in Europe. The essential elements e.g., hydrochloric acid and particulate pre-scrubber, have been proven in decades of operation at a number of power plants.

This subject is further discussed in

Join the Debate on Insitu Rare Earth Recovery

Coal Byproducts including Rare Earths will be a Game Changer

High Chlorine Coals are less costly and can create a Byproduct

The advantages of  using high chlorine coals are the lower cost and the ability to produce a byproduct. This article points out that Illinois coals with 0.2% chlorine content are being burned in many units without extreme corrosion. In fact, it is hard to draw a direct correlation between corrosion and chlorine content. Some coals with 0.3% coal are being successfully utilized. The conclusion is that there are multiple factors creating the corrosion. Steps, such as more even fuel combustion, can be more important than chlorine content.

http://coalcombustion.com/Webpage%20PDF%20Files/Presentations%20and%20Papers%20pdf%20files/Operational%20Considerations%20Burning%20High%20Chlorine%20Coal.pdf

Metso and Outotec Merger creates a Strong Potential Player in “Coal as an Ore” Process

The combined company, comprising Metso Minerals and Outotec but excluding Metso Flow Control, will be called Metso Outotec. Combined, the two had sales in 2018 of about $4.4 billion—and about $4.7 billion when Metso’s recent acquisition of McCloskey is factored in.

Metso Flow Control, meanwhile, will be a pure-play listed entity under the name of Neles with 2018 sales of about $668 million.

The combination of Metso and Outotec creates a major player in minerals and aggregate processing.

Setting up Neles as a separate company makes sense from the perspective that while the measurement equipment will be critical to Metso Outotec, it can continue to work with Neles but make it easier for Neles to sell to other minerals processing companies.

The new CCR rules in the U.S. will create a big opportunity for the combined company. Metso has various products to move flyash and bottom ash.

Dry Drag Chain Conveyors: The dry drag chain conveyor can be applied to precipitators, fabric filters, boiler hoppers  or cyclones for the collection of fly ash.  For dust and fire control, these units handle fly ash in a dust-tight, air-tight construction. One opportunity for the combined company will be coal flyash.

Submerged Chain Conveyors: Bottom ash is continually collected, cooled and dewatered with a submerged chain conveyor. Ash falls constantly from a boiler through a discharge hopper into a waterfilled chamber where the continuous-loop, dual-strand submerged chain conveyor cools it and transports it for disposal.

Outotec is involved in wastewater treatment and supply of biomass and waste to energy plants. It supplies complete plants for the production of high-quality nickel, from a wide range of nickel raw materials. Outotec offers innovative and proven leaching, precipitation, solution purification, solvent extraction and electrowinning technologies, as well as concentrator, sulfuric acid and pyrometallurgical plants and processes.

Hydrochloric acid regeneration has become a vital stage in most chloride process flowsheets. Pyrohydrolysis has been the traditional method of regenerating hydrochloric acid from a variety of chloride solutions, including magnesium, iron and nickel brines.

Outotec has a patent, which demonstrates the company knowledge needed to extract REES.

The invention relates to a method and apparatus for recovering metals from metalliferous starting materials comprising steps of

 

        i.            leaching the metalliferous starting material in chloride-based leaching liquor,

      ii.            withdrawing from the leaching step i) aqueous chloride solution with dissolved  metals,

    iii.            recovering metal value from the aqueous chloride solution in a metal recovery process step,

    iv.            neutralizing hydrogen chloride content of the aqueous chloride solution in the metal recovery process step with adding hydrolyzed ammonia to the process solution so as to form ammonium chloride,

      v.            withdrawing ammonium chloride containing process solution to an ammonium regeneration step where calcium-containing reagent is added to generate calcium chloride and ammonia gas and recycling ammonia back to the metal recovery process step iii),

    vi.            regenerating the CaCl2-solution with H2SOso as to provide an aqueous HCl solution for recycling to the leaching step i).

 

McIlvaine believes there is a good possibility that Coal as an Ore processes for power plants will be very popular. Therefore, this will be a big potential market for Metso-Outotec

June 28

Beneficial uses of Flyash will be Continuously Analyzed

 

Burns & McDonnell says beneficial use of CCR materials can provide economic and environmental benefits, as such uses can reduce costs associated with developing and operating disposal facilities, provide a potential revenue source through the sales of these materials, and reduce the demand for native raw materials through substitution of CCR materials. The firm has experience studying or implementing beneficial use of CCR in the following areas:

·         Underground and surface mine reclamation

·         Coal yard base and pond liner material (roller compacted concrete)

·         Leachate collection system media

·         Protective soil cover systems

·         General fill material

·         Soil stabilization

·         Portland cement concrete

·         Railroad sub-ballast

The McIlvaine Company will be continuing to analyze the potential volume and price for each of these end uses. It will also be looking at other products such as bricks, which are being manufactured in  the Longking dry scrubber process.

Another question would be the value of very pure flyash without any metal, which would result after rare earth elements (REE) recovery.

 

Continuous Fly Ash Transfer System or A2P™ at JEC

 

The traditional types of pneumatic conveying systems utilize numerous moving components such as ash intake valves, swinging or sliding disc valves, butterfly valves, double dump valves, and pressure tanks. These systems also require a moderately sophisticated control system which necessitates a large amount of discrete input/output signals. The systems utilize pressure transmitters, timing devices, and level switches to monitor/control the conveying system’s operational sequence. All of these devices must function reliably and repeatedly for the system to operate effectively.

 

FLSmidth Inc. (Airslide®) A2P system combines two well proven ash handling technologies. This system stores no ash in the precipitator’s collection hopper like traditional ash systems do. As soon as the ash falls into the collection hoppers, it is funneled into the Airslide network that slopes on a slight angle toward an F-K Pump. All of the hoppers feed the Airslide network continuously and simultaneously for nonstop ash removal. The ash residence time from precipitator to storage silo is only a few seconds.

 

JEC’s unit 1, 2, & 3 original ash conveying systems have been exceptionally problematic for Westar Energy since commercial operation began in 1978. The three vacuum systems were never able to remove and transfer the ash from the precipitator hoppers at a rate that ash was being produced. This condition worsened when all of the units increased production and yielded an increased ash make rate of 27 STPH per unit from 23.4 STPH. High maintenance costs also ensued on the existing  vacuum system, which was constantly operating at its full capacity. The total yearly cost to keep the unit 1 fly ash transfer system operational was nearly $235,000.

 

The A2P system compared to traditional ash systems is more advantageous to power plant operations and encompasses improved design features, efficiency, and minimal maintenance. An A2P system will provide a positive return on investment to the end user throughout its operating service.

 

Oklahoma Gas & Electric modifies Bottom Ash Ponds to meet CCR Requirements

 

The Red Rock, Oklahoma plant was upgraded in 2015 to meet CCR rules. Burns & McDonnell provided professional engineering services including evaluation of existing bottom ash settling basins for adequate settling of bottom ash solids as well as structural capacity to meet the requirements of the Coal Combustion Residuals (CCR) Rule. The existing bottom ash settling basins were inadequately sized to limit solids carry-over. Subsequently, an abandoned two-cell coal pile settling basin was repurposed to capture bottom ash solids. Modifications to the bottom ash water system included structural upgrades to the repurposed basin, a jack-and-bore pipe beneath a rail line, overland and below grade HDPE piping, and multiple process modifications to the bottom ash water system. A bottom ash stack-out pad, perimeter walls, and stormwater drain system were designed to containerize bottom ash and waste ash solids for temporary storage.

 

Air Slide has Advantages in removing Precipitator Flyash

 

Westar Energy's Jeffrey Energy Center converted three precipitator fly ash handling systems to air slide style a decade ago. Burns & McDonnell was the engineer. This was the first domestic air slide retrofit on a utility station and has been successfully duplicated at other power plants since that time.

http://www.flyash.info/2007/42youells.pdf

 

Replacement Ceramic Rotary Valves on Limestone Injection saved Money for AC Power

 

F.L Smidth supplied ceramic rotary valves to replace high maintenance valves from a competitor on a limestone injection system in an AC power boiler. The supplier’s rotary valves are smaller than the ones the plant was previously using, but they can feed more limestone with better control and no blowback. The new valves provided a more consistent and reliable feed rate to the furnace.
https://www.flsmidth.com/en-gb/customer-stories/ac-power-ceramic-feeder-case

 

South Africa has Program to utilize Fly Ash

 

The South African electricity public utility Eskom has embarked on a process to increase utilization of the ash produced through the electricity generation process at its coal-fired power stations.

 

In the 2014–2015 financial year, 119.2 million tons of coal was consumed, producing 34.4 million tons (28.9%) of ash. About 7% of the Eskom ash is sold from 6 of the 13 coal-fired power stations. Many stations are currently running out of ash storage space, and expansion of the ash disposal facilities is required, which could affect security of supply because of limited ashing areas.

 

Additionally, legislative requirements lead to extra requirements for ash storage facilities, requiring high capital expenditure. Increased utilization of ash will postpone or ultimately avoid such capital expenditure. The South African legislative framework strictly governs ash utilization. For this reason, Eskom has rejuvenated its Ash Utilization Project.

 

Ash could play a key role in business development, job creation, skills transfer, and localization. The development of small brick-making facilities in close proximity to power stations is ideal. It is imperative to develop new markets that consume high volumes of ash, including road construction and agriculture and land rehabilitation. The backfilling of mines with ash provides an opportunity; tied collieries are located in close proximity to power stations and could absorb high volumes of ash and benefit the ability to rehabilitate mines and mine closures cost efficiently.
http://www.coalcgp-journal.org/papers/2019/1946-0198-11-1-10.pdf

 

High Quality Clinker created with Chinese Flyash

 

This article summarizes the use of two fly ashes in the synthesis of Portland/calcium sulfoaluminate (OPC/CSA or A/CSA) clinkers. They are from the Shentou second power plant located in the Shanxi Province and from the Zhungeer power plant located in Inner Mongolia, China. The Zhungeer ash was collected dry, and the Shentou ash is from a pond. Their chemical compositions differ highly, especially the SiO2 and Al2O3 contents. The high contents of silica and alumina make both ashes candidates as a partial or total substitute for bauxite, an expensive source of alumina, in the production of OPC/CSA clinkers. These particular hybrid clinkers are composed mainly of alite (C3S) and calcium sulfoaluminate (C4A3S), both phases responsible ´ for the high early strength development in OPC and CSA cements, respectively. The production of high-quality OPC/CSA clinkers was produced with both ashes with the additions of hydrated lime, flue gas desulfurization (FGD) gypsum, fluorite, and bauxite at 1250°C for 60 minutes with final composition ranges of 29–41 wt% C3S, 20–22 wt% C2S, 30–45 wt% C4A3S, and 1–4 wt% C4AF.

http://www.coalcgp-journal.org/papers/2019/1946-0198-11-1-59.pdf

 

SonoAsh separation of Carbon in Ash creates Value Opportunities

 

SonoAsh has developed a sustainable, modular, and patented solution for production and impounded coal ash. The technology creates new pathways to make impounded and production coal ash streams into a consistent manufactured product designed to meet regional and individual customer specifications.

https://static1.squarespace.com/static/583f6b6de4fcb526208860e0/t/5cc8f6c49140b793dec8d9bb/1556674269458/2020+to+2070+and+Beyond.pdf

 

Dense Slurry key to ZLD at Hungarian Power Plant

 

The U.S. Environmental Protection Agency identified biological treatment as the baseline treatment technology for FGD wastewater in the ELGs. However, it is becoming evident that bioreactors exhibit high capital and operating costs, occupy significant space, and are sensitive to changes in temperature and pH. Dense slurry ash management can sequester large quantities of FGD wastewater along with the contained contaminants through hydration, encapsulation, and entrainment for a fraction of the cost of traditional treatment. By using dense slurry sequestration of FGD wastewater, off-site discharge of effluent can be avoided altogether. Dense slurry was employed at (among other plants) the Matra Power Plant near Budapest, Hungary, and this technology played a key role in helping the plant achieve zero liquid discharge (ZLD). The Matra project is summarized and data presented that shows how the technology helped the plant achieve ZLD and other environmental objectives.

http://www.coalcgp-journal.org/papers/2018/1946-0198-10-1-1.pdf

 

Putzmeister efficiently moving Dense Coal Ash Sludge at Largest Brown Coal Plant in Europe

 

Alternative forms of fuel are substances, which have a high calorific value like mechanically dewatered sewage sludge, tar, paint sludge or slaughterhouse waste. Putzmeister provides eco-friendly solutions to waste management and on-shore drilling that follow a sustainable and efficient process. It provides modern pumping systems and technology that cater to the oil and gas sector, ash disposal process, sludge incineration systems, cement industry and coal sludging process.

The Belchatow power station in the Polish province of Łódź has a capacity of 5,420 MW, making it Europe’s largest brown coal power station. The landfill site for the ash slurry is around 8-km away from the power station unit itself. The former system with centrifugal pumps was overburdened by both the volume and also the long pumping distance. The wear rate increased drastically. Failure of the pumps, and hence removal of the flue ash, would effectively cause the power station to shut down. The consequences do not even bear thinking about. The reliability of the pump system, then, is paramount.

In 2013, a total of six HSP 25150 HP seat valve pumps featuring the Putzmeister PCF system, each driven by a 800 kW hydraulic unit, were installed for transporting the flue ash of the entire power station. Currently, there are three pump lines in operation and three on stand-by. Some 600 m³ of flue ash slurry are pumped every hour.

Since Putzmeister pumps are capable of conveying much dryer material, the water consumption is considerably less. The HSP pumps manage a 1:1 mixture of flue ash and water, relative to weight. The old centrifugal pumps required a mixture of 1:10.

Previously, the 420 tons of flue ash accumulating per hour had to be mixed with 4,200 tons of water. Today, only 10% of this water quantity is required and so the volume flow rate is drastically reduced. As a result, the power consumption is around half as much as that required for the old pump variant.

https://www.mining-technology.com/contractors/roofing/putzmeister-2/pressreleases/pressputzmeister-coal-power-station/

 

GEA has supplied more than 6,000 MW of Dense Slurry Systems

 

The very first, then intermittently-operated Circumix system was installed in 1990 in Hungary, followed by the first continuous operation mixer in 1992. The first real large-scale system was installed in the Mátra Power Station in 1998 and has been working trouble-free since. Mátra was also the first power station where, after a major upgrade in 2000, FGD by-products were also handled by the Circumix DSS. The first overseas project was commissioned in 2003 in the Jacksonville North Side Generating Station, in the USA in Florida. By 2014, the Circumix systems served over 6,000 MWe coal-fired power plant capacity and have safely processed and deposited more than 60 million cubic meters of dense slurry

 

NAES is the partner in North America. The McIlvaine CCR Decision Guide includes a presentation by Dale Timmons of NAES.

https://www.enexio.com/fileadmin/user_upload/media/ash_handling_systems/EGI_CircumixDense_Slurry_Technology.pdf

 

India is using Flyash for Land Reclamation

 

Many Indian cities are facing a shortage of land, and land reclamation from the sea can give great success for these cities. A large quantity of fly ash  has been permitted to reclaim the land from sea, basically in coastal urban cities. In 2003, the government of India has permitted the use of fly ash for reclamation from the sea. Subject to the rules made under the Environment Protection Act (1986), reclamation from the sea shall be a permissible method of utilization of fly ash. Land reclamation includes maintaining water and air quality, erosion and damage to land properties, minimizing flooding, wildlife and aquatic habitats caused by surface mining. Singapore and Dubai have conducted this type of sea reclamation on a large scale.

Three alternative ways have been investigated to utilize the waste in sea reclamation projects: (1) Singapore and Japan‐based technology, (2) plasma gasification‐based technology and (3) strengthened sediment‐based land reclamation technology.

https://www.intechopen.com/books/coal-fly-ash-beneficiation-treatment-of-acid-mine-drainage-with-coal-fly-ash/challenges-in-recovery-of-valuable-and-hazardous-elements-from-bulk-fly-ash-and-options-for-increasi

China  developing new Flyash uses as Building Industry Slows

 

China’s coal-fired power plants produce about 600 million tons of fly ash annually, which has caused severe economic and environmental problems. This paper first describes briefly the production and utilization status of coal fly ash in China. Then it analyzes the main challenges to the fly ash utilization in China due to the conflict between the huge amount of production of fly ash and the depressed consumption of fly ash, as well as the increasing driving forces in environmental protection. Subsequently, the new developments of fly ash utilization in China, including valuable elements extraction, geopolymer production, fly ash-based ceramics synthesis and soil desertification control are introduced in detail.

CFA can mix with cement, gypsum and clay, etc., to produce autoclaved aerated concrete blocks. Because no high temperature is required, this technique reduces air pollution and decreases energy consumption. Therefore, the above utilization ways are very popular in China.

http://www.ijesd.org/vol8/1057-C3001.pdf

High Aluminum and Iron Flyash can be used to make Flocculants

 

In this work, aluminum and iron existing in coal fly ash were extracted by the method of hydrochloric acid leaching. Effects of solid-liquid ratio, reaction temperature, reaction time, acid concentration, and raw ash mesh on recovery efficiencies of Al2O3 and Fe2O3 were investigated.

 

X-ray diffraction analysis indicated that anhydrite, hematite, mullite and quartz were the dominant minerals in the raw fly ash sample. X-ray fluorescence technique was applied to determine the mass fractions of chemical components in the raw ash and leached residues, while the concentrations of Al2O3 and Fe2O3 in leaching solutions were measured by titration method. The optimal recovery efficiencies of Al2O3 and Fe2O3, obtained under the reaction condition of 95°C, 5 h, acid concentration of 20 wt.%, a solid-liquid ratio of 1:3.5 and raw ash mesh of 400, were 42.75% and 35.10%, respectively. After removing the leached residues, the leaching solutions were employed to manufacture flocculants of polymeric aluminum ferric chloride for treating the oil recovery wastewater from polymer flooding, which possessed high contents of suspended solids (SS) and oils. Microfiltration membrane and ultraviolet spectrophotometer were utilized to determine the contents of SS and oils in water samples. Through adjusting Al/Fe molar ratio to 20:1 and basicity to 70%, the maximum removing efficiencies of SS and oils can be achieved, respectively 96.1% and 91.5%. Moreover, increasing the iron content and basicity of flocculants within certain ranges contributed to improving the settling characteristic of flocs.

https://www.ncbi.nlm.nih.gov/pubmed/29319418

 

U.S. Utilities facing Major Costs in meeting CCR Rule

 

Ameren Missouri will need to spend between $150 million and $200 million through 2023 on a CCR management compliance plan, which includes installing dry ash handling systems, wastewater treatment facilities and groundwater monitoring equipment.

 

Vistra Energy Corp. in February, reported $605 million in "coal ash and other" noncurrent liabilities as of Dec. 31, 2018. Its power generation subsidiary, Luminant Generation Co. LLC, operates coal-fired plants in the Electric Reliability Council Of Texas, Midcontinent ISO and PJM Interconnection wholesale power markets and has no end-use ratepayers from which it can directly recover costs.

 

With 66 total CCR units spread across four states, including landfills, Duke Energy leads the U.S. in both the number of coal ash storage sites and total coal ash volume regulated by federal rule, according to an S&P Global Market Intelligence analysis. Luminant Generation ranks second in terms of CCR units, at 55, and in total volume.

Utilities are facing costs for at least three decades since 67%  are planning to cap the present ponds rather than excavate the ash.

Coal Ash Plan is Published – Missouri

Missouri has 36 coal ash ponds, and they vary in terms of size. Among the smallest is a pond containing boiler slag at Associated Electric Cooperative’s Thomas Hill Energy Center that is 16,000 cubic yards. Ameren Missouri has some of the largest ponds, such as Labadie Energy Center’s pond full of bottom ash, which is 15.8 million cubic yards.

 

The state’s plan, which became available in March, would require utility companies to test groundwater near active coal ash ponds and landfills twice a year. Companies must test first for a short list of chemicals that include boron and sulfate. If there are excessive levels of contaminants detected on the short list, they then test for a longer list of chemicals on the long list, which includes arsenic, lithium and mercury.

Duke planning to Thermally Beneficiate Flyash at H.F. Lee Plant

Duke has applied to install and operate a flyash processing facility consisting of a Staged Turbulent Air Reactor (STAR®) with supporting ancillary sources at the H.F. Lee Steam Electric Plant. This is one of three flyash beneficiation projects in North Carolina (the others are at Duke’s Buck and Cape Fear plants) mandated by HB 630 (Session Law 2016), which modified the closure requirements for coal combustion residuals surface impoundments under the Coal Ash management Act (CAMA) of 2014. The law requires the impoundment owner (Duke) to identify, on or before July 1, 2017, a total of three impoundment sites (located within the State) with ash stored in the impoundments on that date that is suitable for processing for cementitious purposes. The CAMA requires Duke to enter into a binding agreement for the installation and operation of the ash beneficiation projects capable of annually processing 300,000 tons of ash each to specifications appropriate for cementitious products with all ash processed to be removed from the impoundment located at the sites. No later than 24 months after issuance of all necessary permits, operation of each ash beneficiation project is to commence.

The facility will process wet or dry flyash feedstock containing various amounts of unburned carbon into a variety of commercial applications including partial cement replacement and other commercial and industrial applications. The actual design capacity of the H.F. Lee STAR® facility is to produce up to 400,000 tons of flyash product annually.

The STAR® system is a patented technology developed by the SEFA Group Inc. (SEFA) to process feedstock (of any carbon content) like flyash (wet or dry) along with other ingredient materials into a variety of commercial products. These products are used, not only for application as a partial cement replacement, but for many other commercial and industrial applications.

STAR Project Equipment Description

The associated sources of air emissions proposed to support the STAR® system includes the following:

 

·         Ash Basin excavation

·         Ash Handling/Processing

·         Haul Roads

·         Screener

·         Crusher

·         Two diesel engines associated with a Screener and a Crusher

·         Wet ash receiving area and storage shed

·         Wet ash feed hopper

·         Wet ash unloading pile

·         Two External heat exchangers (EHE) (with baghouses)

·         Transfer silo filling and unloading (with bin vent product capture device)

·         Feed silo filling and unloading (with bin vent product capture device)

·         Storage dome filling and unloading (with bin vent product capture device)

·         Loadout silo (with bin vent product capture device)

·         Loadout silo chute 1A (with bin vent product capture device)

·         FGD Byproduct Silo (with bin vent product capture device)

·         FGD Absorbent Silo (with bin vent product capture device)

 

 

Pre-reactor Material Handling Equipment

 

Excavation and processing of materials from the ash ponds to meet the STAR® system flyash ingredient (feedstock) specifications will be under the control of Duke Energy. All flyash reclaimed from an ash pond delivered for use as an ingredient in the STAR® system Must first undergo processing by the owner to be:

 

·         Free of all, but minimal contaminants (e.g., organic debris, slag)

·         Finely-divided and free-flowing;

·         Have a consistent moisture content below 25%; and

·         Have a consistent chemical composition, including organic content measured by loss on ignition.

 

The processing sequence of events will include flyash being excavated and staged to allow for dewatering to ensure a moisture content below 25%. Dewatered flyash will then be screened to remove contaminants (organic debris, slag, etc.), to produce a consistent chemical composition and a finely divided free-flowing material.

 

Wet flyash with a nominal 15% moisture content is delivered via trucks. The wet flyash can be unloaded from the trucks into the storage shed, to a pile, or directly into the feed hopper at up to 70 tons per hour then conveyed to the mechanical conveyance equipment. The material is discharged from the mechanical conveyance equipment into a material delumper unit to reduce large size material. The material is then discharged from the delumper into the external heat exchanger EHE by gravity, where it is continually fluidized using preheated air.

 

The fluidized material is dried in the EHE both by intimate contact with the heated fluidizing air and by direct contact with hot water heat exchangers located in the EHE. The material is discharged from the EHE at less than 2% moisture content and at a temperature range of 150 to 300°F to downstream material-handling equipment (transfer silos).

 

The exhaust air is discharged from each EHE through interconnecting ductwork to a high efficiency baghouse for feedstock recovery and exhaust air treatment to achieve a PM exhaust rate of 0.025 gr/dscf.

 

After leaving the baghouse, the cleaned exhaust air stream passes through interconnecting ductwork to the exhaust air fan before being discharged to the atmosphere. The exhaust air volumetric rate is estimated at approximately 41,550 acfm at 10 inches of water column above atmospheric pressure and at approximately 150-300°F.

 

STAR® Reactor

STAR® technology transforms and recycles coal ash from surface impoundments or ponds into a high-quality, sustainable environmentally-responsible class F flyash product for the concrete industry for beneficial reuse. The process treats flyash in such a way as to lower the “loss on ignition” (LOI – residual carbon in flyash) for use as pozzolan in concrete and can also remove all the carbon in flyash so that the purified mineral material can be used as raw feed material in other specialty products and processes that historically have been unable to use flyash as raw feed material because of the deleterious effect of the residual carbon in flyash. Using recycled STAR® ash in place of Portland cement in concrete reduces the virgin material required in concrete manufacturing, and for every ton of flyash used in concrete, there is approximately one less ton of CO2 released into the atmosphere.

The STAR® process is inherently flexible in that operating parameters can be varied, and different ingredients can be added to produce a desired product. The primary component of the STAR® is a cylindrical refractory-lined reactor vessel in which the majority of the process reactions take place including both chemical and physical reactions. Air required for the process reactions enters through the floor of the STAR® system as well as through the walls at multiple locations.

The raw flyash feedstock and any other ingredients are introduced through the walls of the STAR®. All of the solids and gases exit together at the top of the reactor. Due to the high gas velocity, multiple injection points, and recycled solids returned, there is a significant amount of turbulence created that enhances the mixing of the ingredients and optimizes the reactions.

The STAR® reactor will normally fire auxiliary fuels during system startup and will cut back on auxiliary fuel (i.e., natural gas or propane) as the reactor reaches auto-ignition and self-sustaining conditions. At this point, the residual carbon in the flyash reacts and becomes the heat source and the process is normally self-sustaining except under certain conditions.

The STAR® reactor design capacity is based on two factors: heat input and flyash throughput. The reactor’s short-term maximum heat input capacity is 140 MMBtu/hr. The reactor’s flyash throughput, however, varies based on the percent LOI (residual carbon) content of the flyash, to achieve the 140 MMBtu/hr. maximum design heat input. Duke expects the LOI to be from 6 to 15 percent. Based on the heat content of the residual carbon (14,500 Btu/lb.) the throughput will be limited to achieve the maximum 140 MMBtu/hr. heat input. At 6% LOI and 140 MMBtu/hr. heat input the resulting throughput is 80.5 tons per hour. As the LOI increases, the throughput decreases in order to keep the heat input below the maximum of 140 MMBtu/hr. The reactor system is actually designed to process 75 tons per hour rather than the 80.5 tons per hour, which corresponds to a nominal heat input of 130 MMBtu/hr.

POST-Reactor Material Handling Equipment

 

After exiting the reactor, the flue gas with entrained flyash enters a hot cyclone where the majority of solids are separated from the gas and recycled back to the reactor for temperature control. The flue gas with entrained flyash leaving the hot cyclone is conveyed to an air preheater, which is designed to preheat the incoming process air (by heat recovery) or cool the flue gas/solids mixture, then passes through a flue gas cooler. The cooled flue gas and flyash then passes through a baghouse for product capture, and then exhausts to a dry flue gas desulfurization (FGD) system (using hydrated lime as a reagent) to reduce SO2 emissions. The clean FGD exhaust will then flow to an induced draft fan to be discharged to the atmosphere through a stand-along stack. The captured flyash is pneumatically transferred from the baghouse to either the storage dome or the loadout silo, each equipped with a bin vent, then to a truck loadout station.

Technology –  

https://files.nc.gov/ncdeq/Coal%20Ash/documents/Coal%20Ash/air-quality/lee-review-T43.pdf

June 21

India has a Flyash Disposal Problem

 

India produced about 170 million metric tons of fly ash in 2017. Hundreds of millions of tons are presently stored in ponds, which is causing contamination of ground water. 


Over the last twenty years, the image of fly ash has completely changed from a “hazardous waste” to “Resource Material.” This is achieved due to the focused thrust provided by Fly Ash Mission (FAM) & through Fly Ash Unit (FAU), Department of Science & Technology (DST) India. Fly ash is being used in all fields, whether as whole or in parts. It is being used in the form of cement, for road reclamation and low-lying areas (RLLA), road embankments, mine fillings, ash dyke raising, bricks and tiles, agriculture, concrete and others. The major portions of fly ash are being used mainly for civil and construction, which include cement, mines fillings, concrete, bricks and tiles, road embankments and reclamations.

Indian coal has high ash content, about 30-50%, in comparison to the coal of other countries. The quantum of fly ash production depends on the types of coal used and the operating parameters of the thermal power plants. By the year 2013-14, about 65000 acres of land has already been occupied by ash ponds. While in the current year, 2016-17 the annual production of fly ash in India was about 169.25 MTs and utilization was 107.10 MTs, and about 63 MTs remained unutilized. This huge volume of fly ash requires large areas of land in the form of ash ponds for dumping which may lead to encroachment on agricultural land. Such a huge volume possesses a challenging threat in the form of usage of land, health and environmental hazards. Other problems related to fly ash disposal includes high disposal costs and potential leaching of toxic heavy metals from the areas of dumped fly ash into surrounding soil or ground water.

http://www.ijaerd.com/papers/finished_papers/THE_CURRENT_SCENARIO_OF_THERMALPOWER_PLANTS_AND_FLY_ASH PRODUCTION_AND_UTILIZATION_WITH_A_FOCUS_IN_INDIA-IJAERDV05I0442388.pdf

CCR Costs are at least $50 billion over 100 Years for U.S. Power Plants

With the big potential to beneficiate impounded flyash, the gross cost could be much higher than $50 billion but byproduct sales could put the net cost at less than $50 billon

One estimate of costs was provided several years ago  by Sam Yoder, P.E., and Robynn Andracsek, P.E., Burns & McDonnell (see McIlvaine recorded interview with Robynn)

Compliance costs are significant for short-term and long-term. EPA estimated that the rule would impose 12 regulatory costs: (1) Groundwater monitoring; (2) bottom liner installation; (3) leachate collection system installation and management; (4) fugitive dust controls; (5) rain and surface water run-on/run-off controls; (6) disposal unit location restrictions (including water tables, floodplains, wetlands, fault areas, seismic zones, and karst terrain); (7) closure capping to cover units; (8) post-closure groundwater monitoring requirements; (9) impoundment structural integrity requirements; (10) corrective actions (CCR contaminated groundwater cleanup); (11) paperwork reporting/recordkeeping; and (12) impoundment closures and conversion to dry handling. According to EPA, the rule may affect 414 coal-fired electric utility plants and calculates the cost of the rule over a 100 year period in part because a CCR unit's life spans 40 to 80 years. EPA's estimate of nationwide compliance is an average annualized cost of approximately $509 million per year. However, since these values are for all affected facilities combined, this is of little comparison value for understanding the costs at an individual pond or facility.

One compliance solution is to undergo a wet to dry conversion for which costs can vary drastically depending on the footprint available at each plant ($30 million to $90 million). Similarly, the closure of a pond can vary greatly depending on the size and quantity of CCR material in the pond. Some have seen costs as high as $80 million to $100 million; however, most have been in the $30 million to $50 million range.

Potential corrective actions, such as a pump and treat system or in situ technology, have significant unknown and critically important costs. As utilities are considering future closure options, the possibility of groundwater impacts should be taken into account for those impoundments that will remain active after October 19, 2015. For these impoundments, clean closure could be more cost effective in the long run than a cap-in-place option, which has the potential for years of corrective action. Feasibility studies evaluating the potential for groundwater impacts may be useful at this point in time for strategic cost savings down the road.

Given the short time frame for executing projects associated with the CCR rule, the best information on compliance costs will only be available after the fact.

https://www.power-eng.com/articles/print/volume-119/issue-11/departments/energy-matters/the-real-cost-of-the-ccr-rule.html

 

Duke must decide on excavating all its NC Ash Ponds by August 1

 

North Carolina officials have ordered Duke Energy to excavate all its coal ash storage ponds in the state, saying the utility’s current plan for its coal ash sites does not sufficiently protect groundwater. The directive issued April 1 comes after regulators in other states, including Virginia, issued similar rulings regarding coal ash disposal in those states.

 

Duke, like other U.S. utilities that have operated coal-fired power plants, is spending billions of dollars to clean up its coal ash storage sites. Managing coal ash, primarily the handling and disposal of coal combustion residuals (CCRs), is a major issue for generators. CCRs are the byproducts produced from the combustion of coal or the control of combustion emissions, including fly ash, bottom ash, and other materials that could contain mercury, arsenic, and other toxins.

 

Eight of Duke Energy’s 14 disposal sites in North Carolina have been scheduled for full excavation and closure. The order  from the state’s Department of Environmental Quality (DEQ) says the six remaining power plant sites, including a total of 11 ash ponds, must be completely excavated and closed after what the DEQ said was “rigorous scientific review” by the agency, along with comments from neighboring communities. The DEQ, in its order, said excavation is “the only way to protect public health and the environment.”

 

Duke will need to excavate or cap Ponds at Wabash Energy

 

Duke Energy will need to create a corrective action plan for its coal ash ponds in Indiana after mandatory groundwater testing found the ponds have contaminants at levels higher than groundwater protection standards.

 

On March 1 Duke released its compliance data and reporting on the coal ash ponds at the now shuttered Wabash River Generating Station. The figures show the ash ponds have high levels of arsenic, cobalt and lead.

 

The samples were taken from 37 monitoring wells placed at the base of the coal ponds, and weren’t from drinking water wells, said Angeline Protogere, a spokeswoman for the company.

 

Duke Energy plans to post its corrective action plans in July and hold a public forum to review the plans, she said. “This is a detailed regulatory process. We will evaluate a range of cleanup methods and technologies that are protective of the environment,” Protogere said.

 

Cleanup options include excavating ponds or capping the ponds and keeping the ash in place. Both methods require steps to be taken to protect the water quality of nearby rivers or lakes, Protogere said.

 

We Energies beneficiates Flyash with Reburn System at Pleasant Prairie

 

One challenge We Energies faced in achieving greater percentages of beneficial use was finding sustainable high volume uses for coal ash with high unburned carbon levels. Based mainly on the type of coal burned, the size of the boilers, and the firing technology employed, several units within We Energies’ fleet produced high carbon fly ash and bottom ash, with the majority of this coal ash getting landfilled.

 

The high carbon (or %LOI) was viewed as wasted fuel opportunity, but efforts to improve combustion on these units were limited to small gains. With this existing challenge, We Energies embarked on designing systems at one of its other power plants that could receive the high-carbon ash and meter it into the coal system and boiler with the goal of both recovering the leftover fuel value and beneficiating the ash. Ultimately, this initiative resulted in the installation of both a dry and wet coal ash reburn system at We Energies’ Pleasant Prairie Power Plant.

 

The dry system includes a silo capable of receiving dry fly ash delivered from other power plants in pneumatic tankers. This dry, powdered ash is then metered into distribution pipes and blown into the boiler burners, where it enters the furnace with pulverized coal. The wet coal ash reburn system includes a receiving hopper and conveyor system for handling wet or conditioned ash delivered by end dump style trucks. This coal ash is added to the plant’s coal prior to delivery to the pulverizers, burners, and boiler furnace.

 

https://www.acaa-usa.org/Portals/9/Files/PDFs/ASH02-2015.pdf

NRG loses Lawsuit and may have to remove Impounded Ash

On June 19,  the Illinois Pollution Control Board (IPCB) agreed with environmental groups in their lawsuit against Midwest Generation, LLC, a subsidiary of NRG Energy, alleging that four of its coal-fired power plants contaminated groundwater with harmful chemicals found in coal ash. The pollution at those four coal-fired power plants, located in Waukegan, Joliet, Pekin, and Will County, put the densely populated communities around the plants at risk. This is a major victory in a case started in 2012 by the environmental groups (Sierra ClubEnvironmental Law & Policy CenterPrairie Rivers Network, and Citizens Against Ruining the Environment).

 

The IPCB agreed with the groups’ claim that the contaminants from coal ash at the power plants, including arsenic, boron, sulfate, and other chemicals, routinely exceeded water quality standards and, thus, violated the Illinois Environmental Protection Act. The groups alleged that NRG Energy’s subsidiary Midwest Generation, which has owned or operated the four power plants since 1999, knew about coal ash contaminants both in and outside coal ash ponds and failed to prevent groundwater contamination.

The next step in this case will be a determination of remedy. The environmental groups will fight for the most stringent remedy possible, including a demand for removal of coal ash dumps at the coal-fired power plants.  

Charah Solutions upgrades Unusable Flyash to a High-Quality Product

 

MP618 is a thermal process that immediately reduces loss on ignition (LOI), ammonia, activated carbon and moisture in fly ash. The system can be installed at both operating and non-operating power plants to process current fly ash production, including dry fly ash stored in landfills or wet fly ash stored in legacy ponds, reducing dependence on both.

In addition, MP618 allows for the processing of kiln dust to remove mercury for emissions regulations compliance, so the technology can efficiently deliver a saleable concrete or cement kiln friendly material from existing fly ash streams, with no modifications to the power plant.

Charah claims that MP618 advantages over competing technologies include:

•                     Significantly lower cost profile.

•                     Efficient footprint with self-contained environmental controls that can be deployed in weeks versus years.

•                     Modular design that can be scaled up or down to increase production based on market demand.

•                     Equipment can be used to meet demand without requiring high volumes for cost effectiveness or self-sustaining operation.

•                     Also enables the processing of kiln dust to remove mercury for emissions regulations compliance.

https://www.energycentral.com/o/charah/mp618%E2%84%A2-thermal-process-technology-raises-fly-ash-beneficiation-quality-sales-and

How Big is the Flyash Market?

 

According to one forecaster, the Asia Pacific fly ash market is projected to grow at a CAGR of 6.9% during the forecast period to reach USD 2,868.6 million by 2023. The North American fly ash market is estimated to reach a value of USD 1,065.3 million by 2023, driven by growth in the regions construction sector in recent years and high utilization rate of fly ash. Europe is the world's third-largest fly ash market.

One estimate of the average selling price is $24/ton is only 4 million tons. Since most flyash is used for lower value purposes, the average value may be 1/3 of this price which would match the 13 million ton annual use in the U.S., which is estimated.,

The U.S. generates less than 10% of the worlds flyash. Asia generates 60% soon to reach 70%. Another article in this Alert shows the amount of flyash being generated and used in India. It is very substantial but sold at very low prices with only a small amount for high value concrete use.

McIlvaine is preparing detailed country by country forecasts on flyash and gypsum production.

UK is importing Ash and taking Global View

 

In 2017, the UK generated only one million tons of ash, recovered 0.5 million from landfills and imported  254,000 tons. So demand exceeds supply and this gap will increase with more coal plant retirements.

 

From October 2016, the  UK Quality Ash Association (UKQAA) started to accept members from overseas. As the market for quality ash continues to grow, UKQAA believes the importation of ash will have an important role to play in the future.

While the main role is to protect and maintain UK production and supply, the transition away from coal-fired power over the next five years will have an impact on supply if UKQAA doesn’t intervene. Importation from around the world has huge potential and the association believe its technical advice, guidance, and expertise can help to safeguard future supplies of quality ash—a material that continues to enjoy considerable demand from the construction industry, and for very good reason.